1. Field of the Invention
This invention relates to a printing apparatus capable of both printing characters, on the basis of input data represented by character codes, and plotting figures, on the basis of graphic data applied thereto.
2. Description of the Prior Art
A conventional printing apparatus of the type mentioned above is designed to print characters in dot matrices on the basis of input character codes applied thereto, and to plot figures in dots, on the basis of graphic codes applied thereto. The character codes and graphic codes are generally entered by means of a keyboard. This conventional printing apparatus is deficient in a significant respect, namely, that although it is capable of optionally plotting figures and graphs, the printing quality is unsatisfactory and the characters so printed leave much to be desired.
On the other hand, a typewheel type printing apparatus, equipped with a typewheel having a plurality of type elements, is capable of printing characters of high quality, but, it is incapable of optionally plotting figures and graphs because of the limited number of type elements available on the wheel.
Moveover, a printing apparatus having a recording pen adapted to move in two dimensions, is optionally capable of plotting figures and graphs, but, disadvantageously, the quality of the printed characters made by such an apparatus is unsatisfactory and moreover the recording speed is not sufficiently high.
Thus, there exists in the art, a need for a printing apparatus which can print characters and symbols and plot figures and graphs, both of high quality and with high speed.